Needle actuating mechanism for a knitting machine



.Fan. 31, 1967 E. KRAUSE v NEEDLE ACTUATING MECI'IANISM FOR A KNITTING MACHINE 3 Sheets-$heet 1 Filed Fob.

R O N E v N Erich Kmwse Mmm Md Bet/mm Jan. 31, 1967 E. KRAUSE I 3,301,016

NEEDLE ACTUATING MECHANISM FOR A KNITTING MACHINE Filed Feb. 11, 1964 3 Sheets-Sheet 2 IE. I I In 1 l l 1 I p I 1 M K &\ 5 J [W 5 M B 'Z FIG.1A

IN VE N TOR E r Z c h Krausa B IWWW Jan. 31, 1967 E. KRAUSE NEEDLE ACTUATING MECHANISM FOR A KNITTING MACHINE Filed Feb. 11, 1964 Fig.2

3 Sheets-Sheet 5 INVENTOR Erich Kraase hwnmami 5am M United States Patent O 3,301,016 NEEDLE ACTUATENG MECHANISM FOR A KNTTTHNG MAtIHlNE Erich Krause, Bopiingen, Wurtternherg, Germany, assignor to Universal Maschinenfabrik Dr. Rudolf Schieber G.m.b.H., Westhausen, Wurttcmherg, Germany Filed Feb. 11, 1964, Ser. No. 344,083 Claims priority, application Germany, Feb. 15, 1963, U 9,584 Claims. (Cl. 66-154) This invention relates to knitting machines, and more particularly to a mechanism for actuating movement of the needles of a knitting machine in timed sequence.

In its more specific aspects, the invention is concerned with actuation of longitudinal movement of the several needles in a flat-bed knitting machine in substantially parallel paths in a common plane, but it is not necessarily limited to this type of machine.

It is conventional to actuate the movement of the knitting needles in a flat-bed knitting machine by means of butts on the needles or on jacks which abuttingly engage respective needles. The butts travel along cams which move transversely of the direction of needle movement during operation of the knitting machine. The unavoidable friction between the butts and the cams sets up transverse stresses in the needles and jacks which interfere With the free longitudinal movement of the needles.

It is an object of the invention to provide an actuating mechanism for knitting machine needles which avoids transmission of transverse stresses to jacks or needles.

Another object is the provision of a needle actuating mechanism which avoids the necessity for using jacks.

A further object is the provision of a knitting machine capable of simple automatic needle selection for producing patterned knitted fabrics.

With these and other objects in View, the invention, in one of its aspects, mainly resides in a system of levers mounted on the knitting machine frame for pivoting movement, a portion of each lever engaging an associated needle for longitudinally moving the same when the lever pivots. The levers are actuated by respective cams which are movably mounted on the machine frame.

Other features and the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following description when considered in connection with the accompanying drawings in which:

FIG. 1 shows a knitting machine of the invention in an elevational, partly sectional, fragmentary View; FIG. 1a shows a control arrangement for the device of FIG. 1 partly in elevation and partly in a conventional manner; and

FIG. 2 illustrates another embodiment of the invention in a view corresponding to that of FIG. 1.

Referring initially to P16. 1 of the drawing, there is shown only as much of an otherwise conventional flat-bed knitting machine as is necessary for an understanding of this invention. Only one needle 1 of the multiplicity of latch needles of the machine is illustrated. It is slidably arranged on a needle bed 2 which will be understood to carry the other needles in a common plane with the needle 1. The needle bed 2 is mounted on an element 3 of the stationary supporting frame of the knitting machine, not otherwise shown.

A portion 4 of the needle shank remote from the yarn receiving hooked needle end portion 1a is laterally offset in an approximate U-shape so as to form a laterally open recess. The enlarged rounded head 5 of a rocker arm '6 is movably received in the recess. The arm 6 is pivotally mounted on the machine frame by a fixed pivot pin 9 which also carries another movable rocker arm 7. The

two arms have radial abutment faces 25, 26, and are normally held in the illustrated position in which the faces 25, 26 abut against each other under the pressure of a helical tension spring 8 which connects the arms 6, '7. The arms thus normally move in unison about the pin 9, and consitute a two-armed lever one arm of which is received in the recess of the needle shank.

The free end of the rocker arm 7 carries a cam follower roll 10 which normally engages a circumferential cam face of a disk cam 11. The cam 11 is keyed to a shaft 12 which is journaled in the machine frame and connected to the knitting machine drive in a manner not further illustrated. The roll 10 is urged into engagement with the cam 11 by a helical tension spring 13 which is attached to the machine frame element 3 and to the rocker arm 7. Movement of the roll 10 away from the axis of the shaft 12 is actuated by the disk cam 11. The return movement toward the shaft axis is actuated by the spring 13.

When the cam 11 rotates in the direction of the arcuate arrow, the needle 1 is reciprocated longitudinally in the needle bed 2 between a rest position and a clearing position in which the hooked end portion 1a projects well beyond the edge of the needle bed 2 for taking a yarn 1b as is conventional. The longitudinal movement of the needle 1 may be limited by a back stop 14, and by two front stops 15, 16.

The back stop 14 is mounted in a normally fixed position on the stationary machine frame, but is adjustable in the direction of elongation of the needle 1 as indicated by a double arrow. The location of the front face of the stop 14 in the foremost and rearmost adjusted positions of the stop are indicated by chain dotted lines. In the intermediate position of the back stop 14 illustrated in fully drawn lines, an abutment face 27 on the offset portion 4 of the needle shank abuts against the back stop 14 when the roll 10 is moved away from the shaft 12 by the cam 11. The rocker arm 6 being stopped, the arm 7 is moved away from the arm 6 against the combined tension of the springs 3, 13 while the roll 10 travels over the radially outermost portions of the disk cam 11.

Forward movement of the needle 1 may be arrested in two axially spaced positions by two longitudinally spaced front stops 15, 16 which are movable into and out of the path of the offset shank portion 4 in a direction perpendicular to the direction of needle movement as indicated by double arrows. The front stops may be actuated by an automatic pattern mechanism of the type descriped in my simultaneously filed application Serial Number 344,- 081, for a Knitting Machine with Electromagnetic Needle Selector Mechanism, as shown in FIG. In. Each front stop 15, 16 is pivotally supported on the frame 3 by a pin 29 and connected to the armature 30 of a solenoid 31, and the solenoid windings are energized by a multiple switch arrangement 32 synchronized with the knitting machine drive.

When the front stop 15 is moved into the path of the needle shank portion 4, as indicated in chain-dotted outline, the needle hook 1a is retained within the needle bed substantially as shown in FIG. 1. When the front stop 16 is located in the path of the shank portion 4, the needle hook 1a may be projected outward of the needle bed 2 sufficiently for tucking. The clearing position of the needle 1 is reached during each rotation of the cam 11 if both front stops are in the inoperative position illustrated in FIG. 1. The location of the shank portion 4 in the tuck and clearing positions of the needle 1 are indicated in FIG. 1 in chain dotted outlines.

The forward movement of the needle .1 is actuated by the spring 13 at a speed normally controlled by the disk cam 11. When movement of the needle 1 is arrested by abutment against the front stops 15, 16, the cam 11 is permitted to move away from the roll 10. The arms 6, 7 are held in abutment of their faces 25, 26 by the spring 8.

It will be understood that the knitting machine includes as many levers 7, 8, disk cams 11, and associated springs 8, 13 as there are needles 1. The several cams 1.1 are identical, and are angularly offset relative to each other on the shaft 12 for actuating movement of the needles in the conventional timed sequence. A set of stops 14, 15, 16 is associated with each individual needle. The back stops 14 are not normally shifted during a knitting operation, but the front stops 15, 16 are inserted into the path of the shank portion 4 as needed to produce the desired pattern.

The electromagnetically actuated front stops more fully illustrated in the afore-mentioned simultaneously filed application, are controlled by an endless perforated tape 35 which runs in a closed loop over a battery of microswitches 33 associated with the several magnetic stop actuators 31. The tape is driven by a synchronous motor 34 in circuit with the knitting machine drive. When a perforation in the tape is aligned with a switch, the circuit of the associated stop actuator is closed, and the stop is advanced to the operative position in the manner indicated by chain dotted lines in FIG. 1. Only the switch and circuit associated with one stop are shown in FIG. 1A for the sake of clarity.

Obviously, programming devices other than a perforated tape may be employed to selectively actuate movement of the front stops 15, 16. A magnetic recording tape or a magnetizable information storage drum may be read by heads in a conventional manner. The suitably amplified signals of the reading heads may then be fed to the several magnetic actuators.

A perforated tape may also be employed in conjunction with a light source and a plurality of photoelectric cells. The light of the source reaches the cells through the perforations in the tape. The resulting output signal of the cells is amplified by an amplifier or a relay, and is fed to the respective electromagnetic front stop actuators. Obviously, many other known programming arrangements may be employed for energizing the electromagnetic actuators of the front stops 15, 16 in timed sequence with the rotation of the shaft 12, and of the disk cams mounted thereon.

FIG. 2 shows a flat-bed knitting machine identical with the machine illustrated in FIG. 1 except for the front stop arrangement. The back stop 14 has been omitted from the showing of FIG. 2 for the sake of clarity, but will be understood to be normally positioned as shown in FIG. 1.

The functions of the front stops 15, 16 illustrated in FIG. 1 are assumed by a lever 17 in the knitting machine of FIG. 2. The lever 17 is pivoted on the machine frame by a pin 18 which is parallel to the pin 9 and the shaft 12, and transverse of the direction of elongation of the needle 1. One arm of the lever 17 has two stop faces 16' which are tangential with respect to the pivoting axis of the lever and at different distances from the axis. A helical tension spring 19 is attached to the other arm of the lever 17, and urges the lever to move counterclockwise from the illustrated position.

A contact edge 20 of the lever 17 is urged by the spring 19 into engagement with a cam system which includes a wide belt 22 trained over a drive cylinder 21, and a non-illustrated idler cylinder. The drive cylinder is connected to the main drive of the knitting machine by a motion transmitting train of which only a gear wheel 28 is indicated in phantom view. The movement of the belt 22 thus is synchronized with the rotation of the shaft 12 and of the earns 11 mounted on the shaft.

The belt 22 axially extends over the full width of the needle bed 2, and carries as many rows of cams 23, 24

as there are needles whose longitudinal movement it is desired to control. Only a single row of cams has been shown in FIG. 2 in order not to crowd the drawing. The row of cams extends in the direction of movement of the supporting belt 22.

In the illustrated position of the belt 22, one of the several lower cams 23 engages the contact edge 20 of the lever 17, whereby the abutment face 16 is placed in the path of the shank portion 4, and the needle 1 is arrested in the tuck position although the cam 11 would permit further outward movement of the needle hook 1a under the urging of the spring 13.

As is evident from FIG. 2, engagement of the'contact edge 20 by one of the larger cams 24 while the needle 1 is in the rest position shown in FIG. 1 causes the abutment face 15' of the lever 17 to be placed in the path of the shank portion 4', and the needle 1 to be retained in its rest position during rotation of the disk cam 11. When the contact edge 20 of the lever 17 is moved into engagement with the surface of the belt 22 by the spring 19, the shank portion 4 clears both abutment faces 15', 16, and the needle 1 may be moved by the rocker arm 6 to the clearing position.

It should be understood, of course, that the foregoing disclosure relates only to preferred embodiments of the invention, and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

1. In a knitting machine, in combination:

(a) a support;

(b) a needle bed mounted on said support;

(c) a plurality of elongated knitting needles arranged on said needle bed for longitudinal reciprocating movement in substantially parallel respective paths extending substantially in a common plane,

(1) each needle having a yarn receiving longitudinal front end portion and a shank portion rearwardly from said front end portion;

(2) said shank portion defining a recess therein,

said recess being open transversely of the direction of elongation of said needle;

((1) a lever associated with each of said needles, said lever having two arms and respective abutment faces on said arms;

(e) pivot means on said support having a pivot axis, said two arms being mounted on said pivot means for joint movement about said pivot axis and for movement relative to each other about said axis toward and away from a normal position in which said abutment faces engage each other;

(f) yieldably resilient means connecting said two arms and urging the same toward said normal position;

(g) a shaft mounted on said support for rotation about an axis;

(h) a plurality of cams secured on said shaft for rotation about said axis thereof in axially spaced respective planes;

(i) a cam follower on one of the two arms associated with each needle, the other arm having a head portion spaced from said pivot axis and received in said recess of the associated needle shank portion;

(j) yieldably resilient means for normally holding said cam follower in engagement with a respective one of said cams, whereby the associated needle is normally reciprocated in said path thereof by said head portion when said shaft rotates; and

(k) a plurality of front stop means, each front stop means being movable between an operative position in the path of the associated needle and an inoperative position spaced from said path for limiting forward movement of the associated needle.

2. In a knitting machine as set forth in claim .1 a part of said shank portion being transversely offset to define said recess, said offset part of said shank portion being adapted abuttingly to engage said front stop means during longitudinal movement of said needle.

3. In a knitting machine as set forth in claim 1, each of said front stop means including two stop members individually movable toward and away from respective longitudinally spaced portions of the path of the associated needle.

4. In a knitting machine as set forth in claim 1, each of said front stop means including a stop member having two stop faces normally spaced from each other in the direction of elongation of the associated needle, and actuating means for selectively moving said stop member between a first operative position in which one of said faces is in said path of the associated needle while the other face is spaced from said path, a second operative position in which the other face is in said path, and

an inoperative position in which both faces are spaced from said path.

5. In a knitting machine as set forth in claim 4, said stop member being pivotally mounted on said support, and said actuating means including a cam system engageable with said cam member, said first and second operative positions and said inoperative position of said stop member being angularly spaced from each other.

References Cited by the Examiner UNITED STATES PATENTS 47,579 5/1865 Shirtcliif 66-50 2,252,596 8/1941 Grant 669 2,257,458 9/1941 Ford 66--9 2,984,999 5/1961 Paul 668 MERVIN STEIN, Primary Examiner.

DONALD W. PARKER, Examiner.

R. FELDBAUM, Assistant Examiner. 

1. IN A KNITTING MACHINE, IN COMBINATION: (A) A SUPPORT; (B) A NEEDLE BED MOUNTED ON SAID SUPPORT; (C) A PLURALITY OF ELONGATED KNITTING NEEDLES ARRANGED ON SAID NEEDLE BED FOR LONGITUDINAL RECIPROCATING MOVEMENT IN SUBSTANTIALLY PARALLEL RESPECTIVE PATHS EXTENDING SUBSTANTIALLY IN A COMMON PLANE, (1) EACH NEEDLE HAVING A YARN RECEIVING LONGITUDINAL FRONT END PORTION AND A SHANK PORTION REARWARDLY FROM SAID FRONT END PORTION; (2) SAID SHANK PORTION DEFINING A RECESS THEREIN, SAID RECESS BEING OPEN TRANSVERSELY OF THE DIRECTION OF ELONGATION OF SAID NEEDLE; (D) A LEVER ASSOCIATED WITH EACH OF SAID NEEDLES, SAID LEVER HAVING TWO ARMS AND RESPECTIVE ABUTMENT FACES ON SAID ARMS; (E) PIVOT MEANS ON SAID SUPPORT HAVING A PIVOT AXIS, SAID TWO ARMS BEING MOUNTED ON SAID PIVOT MEANS FOR JOINT MOVEMENT ABOUT SAID PIVOT AXIS AND FOR MOVEMENT RELATIVE TO EACH OTHER ABOUT SAID AXIS TOWARD AND AWAY TO EACH OTHER ABOUT SAID AXIS SAID ABUTMENT FACES ENGAGE EACH OTHER; (F) YIELDABLY RESILIENT MEANS CONNECTING SAID TWO ARMS AND URGING THE SAME TOWARD SAID NORMAL POSITION; (G) A SHAFT MOUNTED ON SAID SUPPORT FOR ROTATION ABOUT AN AXIS; (H) A PLURALITY OF CAMS SECURED ON SAID SHAFT FOR ROTATION ABOUT SAID AXIS THEROF IN AXIALLY SPACED RESPECTIVE PLANES; (I) A CAM FOLLOWER ON ONE OF THE TWO ARMS ASSOCIATED WITH EACH NEEDLE, THE OTHER ARM HAVING A HEAD PORTION SPACED FROM SAID PIVOT AXIS AND RECEIVED IN SAID RECESS OF THE ASSOCIATED NEEDLE SHANK PORTION; (J) YIELDABLY RESILIENT MEANS FOR NORMALLY HOLDING SAID CAM FOLLOWER IN ENGAGEMENT WITH A RESPECTIVE ONE OF SAID CAMS, WHEREBY THE ASSOCIATED NEEDLE IS NORMALLY RECIPROCATED IN SAID PATH THEREOF BY SAID HEAD PORTION WHEN SAID SHAFT ROTATES; AND (K) A PLURALITY OF FRONT STOP MEANS, EACH FRONT STOP MEANS BEING MOVABLE BETWEEN AN OPERATIVE POSITION IN THE PATH OF THE ASSOCIATED NEEDLE AND AN INOPERATIVE POSITION SPACED FROM SAID PATH FOR LIMITING FORWARD MOVEMENT OF THE ASSOCIATED NEEDLE. 